1. Technical Field
The invention relates to central vacuum cleaning systems and in particular to an adapter sleeve for connecting the flexible cleaning hose to an inlet valve which is connected to a centrally installed vacuum producing apparatus. More particularly, the invention relates to an adapter sleeve which is able to be used with a variety of manufacturers inlet valves of varying sizes, slopes and switch pin locations.
2. Background Information
Central vacuum cleaning systems are increasing in popularity in both domestic and commercial buildings wherein a plurality of inlet valves are mounted in either the baseboard area of a wall or in a floor adjacent the wall, which in turn are connected by suitable tubing to a centrally installed vacuum producing apparatus. Most of the inlet valves have a pivotally mounted lid which conceals the inlet opening when the inlet valve is not in use. Certain of these inlet valves have limit switches built into the valve whereupon pivotal movement of the lid to the open position will actuate a switch to energize the remotely located vacuum producing apparatus to produce a vacuum at the inlet valve. Certain other types of inlet valves have a pair of spaced metal contact buttons mounted in the wall of the inlet tube which contact a metal ring on the inserted end of the hose sleeve for completing a circuit to energize the remotely located vacuum producing apparatus. These constructions insure that the vacuum producing apparatus which is usually an electric motor, is energized only when the hose sleeve is inserted into the inlet tube of the inlet valve, and that the motor is automatically deenergized upon removal of the hose sleeve from the inlet valve.
There are various manufacturers of central vacuum cleaning systems presently in the market today, each of which has its own inlet valve and inwardly disposed inlet tube, and electric switch or contact button arrangement. The interior contour, size and configuration of the inlet tubes of these manufacturers inlet valves will vary between the various manufacturers usually enabling only the particular manufacturers hose sleeve to be used satisfactory with its inlet valve. Thus, once a particular central vacuum cleaning system is installed in a building, only the particular manufacturers hose sleeve can be used with the inlet valves which will require the customer to purchase the remaining attachments and apparatus from that manufacturer.
Therefore, in order to capture a larger market share of central vacuum cleaning systems and in particular the various cleaning attachments that can be used with the system, it is desirable that a particular manufacturer's hose sleeve and thus its various cleaning attachments, can be used in most of the other major central vacuum cleaning system manufacturer's inlet valves. Thus, a homeowner having a particular central vacuum cleaning system, need not purchase all of the cleaning attachments and accessories from that manufacturer.
However, due to the various internal lengths, slopes, configurations and type of electrical contacts and the positions thereof, all of which vary somewhat between the manufacturers of central vacuum cleaning systems, an existing manufacturer's hose sleeve will probably only fit its own inlet valve and possibly one or two other manufacturer's inlet valves. It is necessary that the hose sleeve provides a sufficiently tight frictional sealing engagement between the outer surface of the hose sleeve and the interior surface of the inlet tube to provide a vacuum seal and also mechanically maintain the sleeve inserted within the inlet tube. Furthermore the hose sleeve must provide the metal contact area for engaging the internal electrical contact buttons extending into the bore of the inlet tube to energize the vacuum producing apparatus even though these button locations vary between the various manufacturer's of inwall vacuum cleaning systems.
Thus, the need exists for a universal adapter sleeve which can be mounted on the cleaning hose and then sealingly inserted into the inlet opening of the inlet tube of a variety of manufacturer's inlet valves without effecting the sealing efficiency thereof and also provides the electrical contact means.